The background description provided herein is for the purposes of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
A traditional plasma tool includes a radio frequency (RF) generator, an impedance matching circuit, and a plasma chamber. The RF generator is connected to the impedance matching circuit, which is further connected to the plasma chamber. The RF generator generates RF power that is supplied to the impedance matching circuit. The impedance matching circuit matches an impedance of the plasma chamber with that of the RF generator.
During processing of the wafer, various parameters associated with the plasma tool are controlled. It is in this context that embodiments described in the present disclosure arise.